This invention relates generally to coaxial cables and to methods and devices for connecting coaxial cables to other elements. More particularly, it relates to a method and apparatus for connecting a plurality of coaxial cables to a printed circuit board, or to a printed wiring board, using a compact connector.
There are many situations and applications where it is necessary to connect a multicoaxial cable comprised of a large number of small coaxial elements to the traces of a printed circuit board (PCB) or to a printed wiring board (PWB). Generally, the small coaxial elements need to be attached, detached and reattached from the PCB or PWB rather frequently. When doing so, a large number of the smaller elements must mate up with the PCB or PWB in what is typically a very small location.
In the experience of these inventors, the medical field also has a peculiar need for a method and apparatus for connecting multiple coaxial cables to a PCB in a compact space. Specifically, the scan head of a trans-esophageal echocardiac probe requires a plurality of small coaxial elements to be connected to a PCB, or to a PWB, in a detachable manner but in a very confined space. In a mechanism such as the scan head of a trans-esophageal echocardiac probe, anywhere between 10 and 100 coaxial connections are required. Generally, each coaxial cable is rated between 40 and 44 AWG with capacitance in the range of 50 to 100 pF/m. Current probes offer one-dimensional signal resolution. In the future, probes capable of two dimensional imaging may require in excess of 1000 coaxial cables to be terminated. Accordingly, it is important to note that the method and apparatus of the present invention encompasses more than just a single connection. It could provide for a series of connections in which perhaps 1000 coaxes are first funneled into 100 coaxes and the 100 coaxes are then funneled into 10 coaxes.
The center of a coaxial cable carries a signal, but it is not the only part that carries a signal since the shielding of the coaxial cable is also often attached to the PCB. However, and despite this additional functionality, the carrier to which the coaxes are bound is very small so that it does not add significantly to the size of the overall bundle of coaxes. Small size of the invention is extremely important as the cable bundle must be able to be pulled through an endoscopic shaft, which typically has an internal diameter on the order of 6 millimeters.